You have to ask yourself what you're trying to achieve. Are you happy with the sound of the Focals? Then stick with them. Unhappy? Why not? Do they have a good high end, with crisp percussion sounds, natural voices, and clear imaging? If not, then a good pair of bookshelfs might be a good solution. If you're unhappy with the low end, bookshelfs won't help much - look into a subwoofer instead.
Personally, I've always thought that bookshelf+subwoofer was the way to go. However, having bought the DefTech SM45s and been disappointed with them (too harsh in the treble at times), I wouldn't recommend the 65s. But everyone's ears are different: buy them from somewhere you can return them, listen to them at home, and if you like them, you're all set.